Investigation of the multicomponent reaction of 5-hydroxy-2-methyl-4H-pyran-4-one with carbonyl compounds and Meldrum's acid

Herein, we report the studies of the multicomponent reaction of 5-hydroxy-2-methyl-4 H -pyran-4-one with carbonyl compounds and Meldrum's acid. General methods for the synthesis of 6-methyl-3,4-dihydropyrano[3,2- b ]pyran-2,8-diones, 3-(3-hydroxy-6-methyl-4-oxo-4 H -pyran-2-yl)propanoic acid amides and esters, as well as 7-oxo-7 H -furo[3,2- b ]pyran-3-ylacetic acids were elaborated. An efficient synthesis of spiro-condensed dihydropyranones containing 5-hydroxy-2-methyl-4 H -pyran-4-one fragment was developed.